Browsing by Author "Wu, Tsung-Ta"

Now showing 1 - 13 of 13

a-SiGeC Thin Film Photovoltaic Enabled Self-Power Monolithic 3D IC Under Indoor Illumination
(2016)
Kao, Ming-Hsuan
;
Yang, Chih-Chao
;
Wu, Tsung-Ta
;
Hsieh, Tung-Ying
;
Huang, Wen-Hsieh
Low temperature a-SiGeC thin film photovoltaic (TFPV) ambient light-energy harvesters monolithically integrated with high performance 3D sequentially stackable device were demonstrated in this article. The 3D stackable device with threshold voltage engineering and driving current boosting technologies enable excellent current controllability to achieve low I-off and high I-on operation condition for integrated circuit design. The monolithically stacking of Si thin-film energy harvester, which provide output power (21.93uW/cm(2)) under 450 lux indoor illumination, envisions self-power and low cost 3D(+)IC for internet of things.
CIGS solar cell integrated with high mobility microcrystalline Si TFTs on 30X40 cm(2) glass panels for self powered electronics
(2012-01-01)
Shen, Chang-Hong
;
Shieh, Jia-Min
;
Wu, Tsung-Ta
;
Huang, Jung Y.
;
Huang, Che-Hsuan
For the first time, we report a novel self-powered TFT panel (30X40cm(2)) by integration of sputtering/non-toxic Se vapor selenization copper-indium-gallium-selenide (CIGS) solar cell (conversion efficiency of 8%) and high electron-mobility (172 cm(2)/V-s) micro-crystalline (mu c)-Si TFTs.
Dinuclear Lanthanide(III)-m-ODO2A-dimer Macrocyclic Complexes: Solution Speciation, DFT Calculations, Luminescence Properties, and Promoted Nitrophenyl-Phosphate Hydrolysis Rates
(2018-04-25)
Chang, C. Allen
;
Lee, Hwa-Yu
;
Lin, Syue-Liang
;
Meng, Ching-Ning
;
Wu, Tsung-Ta
Potentiometric speciation studies, mass spectrometry, and DFT calculations helped to predict the various structural possibilities of the dinuclear trivalent lanthanide ion (Ln(III), Ln=La, Eu, Tb, Yb, Y) complexes of a novel macrocyclic ligand, m-ODO2A-dimer (H4L), to correlate with their luminescence properties and the promoted BNPP and HPNP phosphodiester bond hydrolysis reaction rates. The stability constants of the dinuclear Ln(2)(m-ODO2A- dimer) complexes and various hydrolytic species confirmed by mass spectrometry were determined. DFT calculations revealed that the Y2LH-1 and the Y2LH-2 species tended to form structures with the respective closed- and open-form conformations. Luminescence lifetime data for the heterodimetallic TbEuL system confirmed the fluorescence resonance energy transfer from the TbIII to Eu-III ion. The internuclear distance RTbEu values were estimated to be in the range of 9.4-11.3 a ( pH 6.7-10.6), which were comparable to those of the DFT calculated open-form conformations. Multiple linear regression analysis of the kobs data was performed using the equation: k(obs),(corr.)=k(obs) k(obs),(OH)=k(Ln2)LH(M)-(>1) [Ln(2)LH(-1)]broken vertical bar k(Ln2LH-2) [Ln(2)LH(-2)] for the observed Ln(2)L-promoted BNPP/HPNP hydrolysis reactions in solution pH from 7 to 10.5 (Ln=Eu, Yb). The results showed that the second-order rate constants for the Eu2LH-2 and Yb2LH-2 species were about 50-400 times more reactive than the structural analogous Zn-2(m-12N(3)O-dimer) system.
Heterogeneously integrated sub-40nm low-power epi-like Ge/Si monolithic 3D-IC with stacked SiGeC ambient light harvester
(2014)
Shen, Chang-Hong
;
Shieh, Jia-Min
;
Huang, Wen-Hsien
;
Wu, Tsung-Ta
;
Chen, Chien-Fu
For the first time, we report heterogeneously integrated sub-40nm epi-like Ge/Si monolithic 3D-IC with low-power logic/NVM circuits and efficient photovoltaic energy harvester. Threshold voltage engineering and driving current boosting technologies enable stackable Ge/Si UTB (< 15nm) MOSFETs, CMOS inverter and SRAM (SNM=270mV@0.7V) achieve low operation voltage. Stackable 1-T NVM with high speed (100ns) and low driving-voltage operation provide power-off storage while SRAM serve as power-on working memory. 100% aperture ratio SiGeC ambient light energy harvester with maximum output power of 7mW/cm(2) layered on the monolithic 3D-IC chip envisions a self-powered monolithic 3D-IC technology for advanced low-power wire-less sensor networks, wearable devices, and devices for Internet of Things.
High Performance and Low power Monolithic Three-Dimensional Sub-50 nm Poly Si Thin film transistor (TFTs) Circuits
(2017-05-02)
Wu, Tsung-Ta
;
Huang, Wen-Hsien
;
Yang, Chih-Chao
;
Chen, Hung-Chun
;
Hsieh, Tung-Ying
Development of manufacture trend for TFTs technologies has focused on improving electrical properties of films with the cost reduction to achieve commercialization. To achieve this goal, high-performance sub-50 nm TFTs-based MOSFETs with ON-current (I-on)/subthreshold swing (S.S.) of 181 mu A/mu m/107 mV/dec and 188 mu A/mu m/98 mV/dec for NMOSFETs and PMOSFETs in a monolithic 3D circuit were demonstrated by a low power with low thermal budget process. In addition, a stackable static random access memory (SRAM) integrated with TFTs-based MOSFET with static noise margins (SNM) equals to 390 mV at V-DD = 1.0 V was demonstrated. Overall processes include a low thermal budget via ultra-flat and ultra-thin poly-Si channels by solid state laser crystallization process, chemical-mechanical polishing (CMP) planarization, plasma-enhanced atomic layer deposition (ALD) gate stacking layers and infrared laser activation with a low thermal budget. Detailed material and electrical properties were investigated. The advanced 3D architecture with closely spaced inter-layer dielectrics (ILD) enables high-performance stackable MOSFETs and SRAM for power-saving IoT/mobile products at a low cost or flexible substrate.
Hydrolysis and DFT structural studies of dinuclear Zn(II) and Cu(II) macrocyclic complexes of m-12N(3)O-dimer and the effect of pH on their promoted HPNP hydrolysis rates
(2016)
Chang, C. Allen
;
Wu, Tsung-Ta
;
Lee, Hwa-Yu
;
生物科技學系
;
Department of Biological Science and Technology
The synthesis of the ligand, m-12N(3)O-dimer (1,3-bis(1-oxa-4,7,10-triazacyclododecan-7-yl)methyl)benzene, L), and the stability and hydrolysis constants of its dinuclear Zn(II) and Cu(II) complexes are reported, in addition to the effect of pH on HPNP (2-hydroxypropyl-4-nitrophenylphosphate) hydrolysis reaction rates promoted by these complexes. Various structural possibilities of the [Zn2L] and [Cu2L] hydrolytic species derived from solution equilibrium modeling are predicted from density functional theory (DFT) studies to correlate with the promoted HPNP hydrolysis reaction rates and to establish the structure-function-reactivity relationship. Upon deprotonation [Zn2L(OH)](3+) tends to form a structure with a closed-form conformation where it is not possible for para-isomers. At pH >8, the formation of the closed-form [Zn2L(OH)(2)](2+) and [Zn2L(mu-OH)(OH)(2)](+) species led to faster promoted HPNP hydrolysis rates than the [Zn2L(OH)](3+) species. On the other hand, the observed rates of the Cu2L-promoted HPNP hydrolysis reaction were much slower than those of the [Zn2L]-promoted ones due to formation of the inactive, di-mu-OH- bridged closed-form [Cu2L(mu-OH)(2)](2+) structure at high pH. The effects of solvent molecules and the use of higher DFT computation levels, i.e., M06 and M06-2X, in conjunction with cc-pVDZ and cc-pVTZ basis sets on the DFT-predicted structures for both [Cu(12N(4))(H2O)](2+) and [Zn(12N(3)O)(H2O)(2)](2+) complexes were also evaluated and compared with those using the B3LYP/6-31G* method. [GRAPHICS]
Improved Efficiency of a Large-Area Cu(In,Ga)Se-2 Solar Cell by a Nontoxic Hydrogen-Assisted Solid Se Vapor Selenization Process
(2014-04-09)
Wu, Tsung-Ta
;
Hu, Fan
;
Huang, Jyun-Hong
;
Chang, Chia-ho
;
Lai, Chih-chung
A nontoxic hydrogen-assisted solid Se vapor selenization process (HASVS) technique to achieve a large-area (40 X 30 cm(2)) Cu(In,Ga)Se-2 (CIGS) solar panel with enhanced efficiencies from 7.1 to 10.8% (12.0% for active area) was demonstrated. The remarkable improvement of efficiency and fill factor comes from improved open circuit voltage (V-oc) and reduced dark current due to (1) decreased interface recombination raised from the formation of a widened buried homojunction with n-type Cd-cu participation and (2) enhanced separation of electron and hole carriers resulting from the accumulation of Na atoms on the surface of the CIGS film. The effects of microstructural, compositional, and electrical characteristics with hydrogen-assisted Se vapor selenization, including interdiffusion of atoms and formation of buried homojunction, were examined in detail. This methodology can be also applied to CIS (CuInSe2) thin film solar cells with enhanced efficiencies from 5.3% to 8.5% (9.4% for active area) and provides a facile approach to improve quality of CIGS and stimulate the nontoxic progress in the large scale CIGS PV industry.
Logic/Memory Hybrid 3D Sequentially Integrated Circuit Using Low Thermal Budget Laser Process
(2015)
Yang, Chih-Chao
;
Hsieh, Tung-Ying
;
Huang, Wen-Hsien
;
Wu, Tsung-Ta
;
Wang, Hsing-Hsiang
High performance 3D sequentially stackable nanowire FETs and non-volatile memories (NVMs) with threshold voltage engineering and driving current boosting technologies were demonstrated by using low thermal budget nanosecond laser crystallization and laser activation technologies. The local heating laser process without damaging the underlying device/circuit realizes the across -layer and in -layer integration of high-speed 3ps logic circuits and 1-T 100ns plasma-MONOS NVMs as well as low driving-voltage 6T SRAMs with static noise margin (SNM) of 280 mV. Such logic/memory hybrid 3D sequentially integrated circuit provides power efficient computing and storage. Moreover, the monolithically stacking of Si thin-film energy harvester envisions lower power and low cost 3D(+)IC for internet of things.
Monolithic 3D Chip Integrated with 500ns NVM, 3ps Logic Circuits and SRAM
(2013)
Shen, Chang-Hong
;
Shieh, Jia-Min
;
Wu, Tsung-Ta
;
Huang, Wen-Hsien
;
Yang, Chih-Chao
For the first time, a sequentially processed sub-50nm monolithic 3D IC with integrated logic/NVM circuits and SRAM is demonstrated using multiple layers of ultrathin-body (UTB) MOSFET-based circuits interconnected through 300nm-thick interlayer dielectric (ILD). High-performance sub-50nm UTB MOSFETs using deposited ultra-flat and ultra-thin (20nm) epi-like Si enable across-layer and in-layer high-speed 3ps logic circuits and 1-T 500ns plasma-MONOS NVMs as well as 6T SRAMs with static noise margin (SNM) of 280 mV and reduced footprint by 25%. Closely stacked monolithic 3D circuits envision advanced high-performance, rich function, and low power intelligent mobile devices.
Multi-functional stacked light-trapping structure for stabilizing and boosting solar-electricity efficiency of hydrogenated amorphous silicon solar cells
(2013-08-12)
Huang, Wen-Hsien
;
Shieh, Jia-Min
;
Pan, Fu-Ming
;
Shen, Chang-Hong
;
Huang, Jung Y.
A sandwiched light-trapping electrode structure, which consists of a capping aluminum-doped ZnO (AZO) layer, dispersed plasmonic Au-nanoparticles (Au-NPs), and a micro-structured transparent conductive substrate, is employed to stabilize and boost the conversion-efficiency of hydrogenated amorphous silicon (a-Si:H) solar cells. The conformal AZO ultrathin layer (5 nm) smoothened the Au-NP-dispersed electrode surface, thereby reducing defects across the AZO/a-Si:H interface and resulting in a high resistance to photo-degradation in the ultraviolet-blue photoresponse band. With the plasmonic light-trapping structure, the cell has a high conversion-efficiency of 10.1% and the photo-degradation is as small as 7%. (C) 2013 AIP Publishing LLC.
Record-high 121/62 mu A/mu m on-currents 3D stacked epi-like Si FETs with and without metal back gate
(2013)
Yang, Chih-Chao
;
Chen, Szu-Hung
;
Shieh, Jia-Min
;
Huang, Wen-Hsien
;
Hsieh, Tung-Ying
A sequential layered integration technology that can fabricate 3D stackable epi-like Si FETs with and without metal back gate (MBG) under sub-400 degrees C are proposed in this article. With laser crystallized epi-like Si and CMP thinning processes for channel fabrication, 3D stackable ultra thin body (UTB) n/p-MOSFETs with low-subthreshold swings (88 and 121 mV/dec.) and high on-currents (121 and 62 liA/Iim) are demonstrated. With additional metal back gate structure, UTB devices can be desirably operated in a positive or negative threshold voltage range with gamma values of 0.51 (n-MOSFETs) and 0.56 (p-MOSFETs) for favoring its applications in 3D logic circuits. In addition, such thin and high quality channel and metal back gate scheme is not only promising for conventional p-n junction device but also junctionless (JL) scheme, which can simplify the fabrication and achieve further scaling.
Suppression of surface recombination in CuInSe2 (CIS) thin films via Trioctylphosphine Sulfide (TOP:S) surface passivation
(2016-03)
Luo, Shi
;
Eisler, Carissa
;
Wong, Tsun-Hsin
;
Xiao, Hai
;
Lin, Chuan-En
CuInSe2 (CIS) solar cells are promising candidates for thin film photovoltaic applications, one key limitation in their performance is surface recombination in these thin films. We demonstrate that passivating CIS films with Trioctylphosphine Sulfide (TOP:S) solution increases photoluminescence (PL) intensity by a factor of similar to 30, which suggests that this passivation significantly reduces surface recombination. X-ray photoelectron spectroscopy (XPS) reveals that TOP:S forms both -S and -P bonds on the CIS film surface, which leads to a similar to 4-fold increase in the surface Na peak intensity. This value is significantly higher than what would be expected from high temperature annealing alone, which has been linked to improvements in surface morphology and device efficiency in CIGS solar cells. We use Energy Dispersive X-ray Spectroscopy (EDS) to measure the solid-state transport of Na within CIS films with and without passivation. EDS spectra on CIS film cross-sections reveals a saddle-shaped Na profile in the as fabricated films and a concentration gradient towards the film surface in the passivated films, with 20% higher surface Na content compared with the unpassivated films. We employ Hybrid (B3PW91) Density Functional Theory (DFT) to gain insight into energetics of Na defects, which demonstrate a driving force for Na diffusion from bulk towards the surface. DFT Calculations with TOP:S-like molecules on the same surfaces reveal a similar to 1eV lower formation energy for the Na-cu defect. The experiments and computations in this work suggest that TOP:S passivation promotes Na diffusion towards CIS film surfaces and stabilizes surface Na defects, which leads to the observed substantial decrease in surface recombination. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Toward high efficiency and panel size 30 x 40 cm(2) Cu(I,Ga)Se-2 solar cell: Investigation of modified stacking sequences of metallic precursors and pre-annealing process without Se vapor at low temperature
(2014-11-01)
Wu, Tsung-Ta
;
Huang, Jyun-Hong
;
Hu, Fan
;
Chang, Chia-ho
;
Liu, Wen-Long
Modified stacking sequence of precursors and pre-annealing process on Se vapor at low temperature were applied to Cu(ln,Ga)Se-2 (CIGS) solar. The remarkable improvement of efficiency (5.53-10.10% and further 11.04%) and open circuit voltage (0.41 V-0.53 V and further 0.56 V) comes from a compact, smooth microstructure, and modified depth profile of Ga with suitable thickness of CuGa multi-stacking layers in the top of precursors as well as surface bandgap enhancement via pre-nnealing process without Se vapor followed by a specific non-toxic hydrogen-assisted solid Se vapor selenization process. The effects of microstructural, compositional and electrical characteristics of Ga distribution including accumulation and interdiffusion were examined in detail. Finally, a large-area (40 x 30 cm(2)) CIGS solar cell efficiency with improved open circuit voltage (V-OC) and fill factor (FE) of 36% and 14% has been demonstrated, yielding a promising efficiency of similar to 11.04%. (C) 2014 Elsevier Ltd. All rights reserved.